What is the original use case?
Maybe knowing that would help inform decisions on whether files and/or directories contain themselves and whether parameters need to exist or not.
Note that the behaviour of getCanonicalFile() may depend on whether or not the file exists, from the Javadoc:
The canonical form of the pathname of a nonexistent file or directory may be different from the canonical form of the same pathname after the file or directory is created. Similarly, the canonical form of the pathname of an existing file or directory may be different from the canonical form of the same pathname after the file or directory is deleted.
I don't like the recursive implementation; also it should not be necessary to call getCanonicalFile() multiple times.
It's also unsafe to call it multiple times as the representation may potentially change because of the above.
The io-291.diff patch contains tabs, and is an Eclipse workspace-relative patch so is difficult for anyone else to apply.
Both patches contain @author tags, which we discourage.